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1.
罗利群 《植物研究》2005,25(3):260-261
秤锤树属(安息香科)一新变种--乐山秤锤树(Sinojackia xylocarpa Hu var. leshanensis L. Q. Luo)在中国四川被发现。  相似文献   

2.
杜仲,秤锤树花粉的超低温贮藏研究   总被引:10,自引:1,他引:9  
本文研究了影响杜仲(Eucommia ulmoides Oliv.)和秤锤树(Sinojackia xylocarpa Hu.)花粉超低温贮藏的一些因素,包括花粉含水量、贮藏时间、冻解方法等。利用差热分析(DTA)技术预测花粉在液氮(LN)中安全贮藏含水量的范围。结果表明,含水量的影响最显著。DTA 有望用于预测花粉在 LN 中安全贮藏含水量的范围。  相似文献   

3.
为了解狭果秤锤树(Sinojackia rehderiana)群落的物种共存机制,研究了群落0.5hm~2样地内5主要树种的空间分布格局和种间关联性。结果表明,香樟(Cinnamomum camphora)、紫弹树(Celtis biondii)处于群落上层,尾叶冬青(Ilex wilsonii)在群落中层,下层以狭果秤锤树、瓜木(Alangium platanifolium)为主。狭果秤锤树、香樟、尾叶冬青、瓜木在小尺度上均为聚集分布,随着尺度的增大呈现出均匀分布或随机分布的趋势;紫弹树在全部尺度上为随机分布。尾叶冬青、瓜木在较小尺度上与狭果秤锤树的空间分布呈负相关,而香樟、紫弹树与狭果秤锤树则在较大尺度上呈负相关性,香樟、紫弹树、尾叶冬青、瓜木两两之间均无明显空间相关性。因此,推断密度制约和种子扩散限制对狭果秤锤树群落空间格局形成起作用,生境异质性的影响没有明显表现出来,群落尚未达到稳定状态。  相似文献   

4.
以南京老山1 hm 2样地秤锤树(Sinojackia xylocarpa)天然种群为研究对象,运用成对g(r)函数,选择完全随机模型、异质泊松模型与先决条件零模型,分析秤锤树种群结构和空间分布格局及其空间关联性,从空间格局角度来深入认识其种群结构和分布格局及形成该格局可能存在的机制并提出保护建议。结果表明:(1)秤锤树天然种群中小径个体数量占优,属于增长型种群。(2)种内空间分布研究中,基于完全随机模型分析,秤锤树种群在尺度0~26 m时为聚集分布,尺度29~30 m时为均匀分布;基于异质泊松模型分析,秤锤树种群在0~23 m时为聚集分布,尺度27~30 m时为均匀分布。秤锤树空间分布表现为由聚集分布向均匀分布变化。(3)主要种间关联性研究中,秤锤树与朴树(Celtis sinensis)的种间关联性表现为小尺度下负关联,随着空间尺度的增加变为正关联。秤锤树与黄连木(Pistacia chinensis)和秤锤树与三角槭(Acer buergerianum)的种间关联性大致相同,基本为大尺度下正关联,偶尔出现负关联和无关联。上述结果表明,秤锤树种群更新状况良好,种群空间分布以聚集分布为主,其主要受种间竞争、扩散限制与密度制约的影响。基于种群现状开展就地保护与适当干扰其生存群落,是濒危物种秤锤树的科学有效的保护措施。  相似文献   

5.
秤锤树属(Sinojackia)是中国特有属,包括7个物种,各物种的种群及个体数量均较少,预测其潜在适宜分布区及其主要影响因素对制定保护措施至关重要。该研究在全面收集秤锤树属植物分布位点数据的基础上,结合气候、土壤和植被数据,运用物种分布模型(MaxEnt)和ArcGIS,预测该属植物当前的分布范围以及未来(2050s和2070s)潜在分布区的变化,分析影响该属植物分布的主要环境变量。预测结果显示:(1)当前秤锤树属高适宜地区主要在我国的亚热带地区,分布在长江中下游平原,包括湖南、浙江的大部分地区,河南、安徽和江苏南部地区以及湖北和江西两省交界处,四川、贵州零星分布着高适宜度位点;纬度范围为25.42°~31.84°N。(2)当前秤锤树属的高适宜性(0.665)生境面积仅为4.07×104 km2,占国土面积的4.23%,分布区极为狭窄。未来(2050s和2070s)的高适宜分布地区将大幅度缩减,其中在2070s的RCP8.5排放情景下减少最多。(3)随着温度的上升,秤锤树属植物有向高纬度迁移的趋势。研究结果可为濒危植物的就地保护提供科学依据,同时也可为其迁地保护位点的选择提供参考。  相似文献   

6.
细果秤锤树(Sinojackia microcarpa)是中国特有极小种群植物之一,属国家Ⅱ级重点保护植物。为揭示该种群的生存潜力与濒危机制,为种群保护提供依据,采用样地调查法在浙江省建德市细果秤锤树自然集中分布区进行野外调查,以空间代替时间研究了细果秤锤树种群的结构特征,绘制了种群静态生命表及种群存活曲线,并应用种群动态和时间序列量化预测种群未来发展态势。结果表明:(1)细果秤锤树的径级、高度和冠幅结构均表明该种群龄级结构总体呈衰退型,种群幼年树淘汰率较高,中年树到老年树过渡阶段适应力增强,生长情况较前期稳定。(2)生活曲线属Deevey-Ⅲ型,早期死亡率高,生存分析揭示细果秤锤树种群具有前期锐减的动态特征。(3)时间序列分析预测在未来2、4、6、8个龄级后,细果秤锤树的年龄结构存在幼年个体数下降,中、老年树占优势的衰退风险。(4)种群动态指数表明该种群结构总体波动大,抗外界干扰能力较弱,环境对个体的选择作用较强。为促进种群自然更新,应加强就地保护措施,降低人为干扰对个体生存环境的威胁,提高幼苗至幼树转化率,实现种群恢复。  相似文献   

7.
黄梅秤锤树(Sinojackia huangmeiensis J.W.GeX.H.Yao)是我国120个极小种群野生植物之一。本研究运用独立样本t检验和贝叶斯方差分析比较黄梅秤锤树仅存的1个迁地保护种群和1个野生种群的环境条件、果实形态性状和果实元素含量。结果显示,迁地保护种群和野生种群同处于亚热带地区,年均温和年降水量基本一致。迁地保护种群的果实长度、宽度和长宽比均显著大于野生种群;2个种群在果实重量上呈现相同的趋势,但差异不显著。迁地保护种群在果实形态性状方面,种内变异程度不低于野生种群;土壤和果实中绝大多数元素(Ni元素除外)的含量在2个种群间的变化规律不一致。研究结果表明该物种的迁地保护基本成功,但存在迁地保护种群较小的问题。  相似文献   

8.
秤锤树的组织培养和快速繁殖   总被引:6,自引:0,他引:6  
1植物名称秤锤树(Sinojackia xylocarpa). 2培养材料当年生枝条的腋芽或茎尖. 3培养条件芽萌动启动培养基:(1)改良的MS(除钙盐外,其余大量元素用MS的3/4量) 6-BA 1.5mg·L-1(单位下同) TDZ 0.05 IBA 0.1;(2)改良的MS 6-BA 1.0 TDZ 0.05 IBA 0.1.分化培养基:(3)改良的MS 6-BA 1.0 TDZ 0.05 IBA 0.05;(4)改良的MS 6-BA 0.5 TDZ 0.05 IBA 0.05;(5)改良的MS 6-BA 0.5 TDZ 0.05 IBA 0.1.生根培养基:(6)1/2MS IBA 0.3;(7)1/2MS IBA 0.5;(8)1/2MS IBA 1.0;(9)1/2MS IBA 0.3 NAA 0.5;(10)1/2MS IBA 0.5 NAA 0.3.以上培养基含3%食用白糖(其中生根培养基加2%食用白糖)、0.7%卡拉胶,pH 5.8~6.0.培养温度25~28℃,光照时间12 h·d-1,光照度2 000 lx.  相似文献   

9.
秤锤树的核型研究及其减数分裂过程的观察   总被引:11,自引:1,他引:11  
观察研究了秤锤树有丝分裂和减数分裂的细胞学特征。秤锤树核型为2n=2x=24=4m 7sm(2SAT) 1st,属于较为原始的2A型。有丝分裂间期核为复杂染色中心型,前期出现B染色体,中期染色体中等大小。减数分裂中期具12对正常的二价体,但后期I和后期Ⅱ均有染色体异常现象发生。统计断片、落后染色体和染色体桥出现的比例与花粉粒败育性比例比较一致,表明秤锤树的小孢子在发生和发育过程中较高频率的败育现象可能存存一常的细胞学原因.  相似文献   

10.
肉果秤锤树(Sinojackiasar-cocarpaL.Q.Luo)属安息香科秤锤树属,是1992年发表的新种。秤锤树属是中国特有属,该种又是秤锤树属中唯一具肉质果实的种,在学术研究上有重要意义;而且它的花和果实都具较高的观赏价值,可引种为园林树种。总之它是一个学术上、应用上都有价值的种。然而,该种从发现之日起即处于濒危状态。到目前为止,野生成年树及幼苗仅存不足10株,散布于一处狭窄的约500平方米的范围内,而开花结果的两株大树一株已近死亡,另一株树基已被白蚊蛀空,如果再遇人为破坏或其它意外情况,则这一新发现的物种…  相似文献   

11.
Purpose: The purpose of this study was to determine whether α-galactosylceramide (α-GalCer), a synthetic glycolipid agonist of natural killer T (NKT) cells, can ameliorate exercise-induced immune imbalance. Methods: Eight-week-old female Sprague-Dawley rats were trained with a progressively increasing load for 9 weeks. At 36 h and at 7 d after training, groups of rats were euthanized. The whole blood was used to detect hemoglobin(Hb), plasma was analyzed for hormones testosterone(T) and corticosterone(C), and spleen was harvested for detecting NKT cells and interferon-γ (IFN-γ) and interleukin (IL)-4 producing cells. Results: Two-way analysis of variance (ANOVA) showed significant differences between training and time in Series 1. The results showed, at 36h after training, that the decrease in Hb, T and C concentration reflected overtraining or excessive exercise. At 7 d after training, NKT cell populations decreased, and a T helper 1/T helper 2 (Th1/Th2) lymphocyte imbalance occurred. In Series 2, α-galactosylceramide (α-GalCer), an NKT cell activator was found to enhance NKT cell numbers by 69% and shift the Th1/Th2 lymphocyte imbalance by observably decreasing the frequency of IL-4 secreting cells. Conclusion: These data showed that, in addition to Th1/Th2 self-regulation, α-GalCer played an important modulatory role in the exercise-induced Th1/Th2 lymphocyte imbalance, which may be correlative with NKT immunoregulatory cells.  相似文献   

12.
长果安息香属和秤锤树属植物叶片脉序研究   总被引:4,自引:0,他引:4  
杨庆锋  蔡雪珍  陈涛   《广西植物》1997,17(2):145-148
本文观察和描述了单种属长果安息香属和秤锤树属5种植物的叶脉特征。结果表明,两属植物的脉序特征比较一致;但各种之间也存在一些差别,根据这些差别可编出分种检索表;长果安息香与秤锤树属各种的三级脉特征明显不同,支持成立长果安息香属  相似文献   

13.
范黎  刘虹  刘波 《菌物学报》2005,24(3):340-343
报告隶属于柄灰包目Tulostomatales、柄灰包科Tulostomataceae、柄灰包属Tulostoma的我国新记录种石灰色柄灰包T.cretaceum、隐柄灰包T.evanescens、惑柄灰包T.perplexum和美丽柄灰包T.pulchellum,并附有插图和照片。  相似文献   

14.
The macrophage mannose receptor (MR) is a pattern recognition receptor of the innate immune system that binds to microbial structures bearing mannose, fucose and N-acetylglucosamine on their surface. Trypanosoma cruzi antigen cruzipain (Cz) is found in the different developmental forms of the parasite. This glycoprotein has a highly mannosylated C-terminal domain that participates in the host-antigen contact. Our group previously demonstrated that Cz-macrophage (Mo) interaction could modulate the immune response against T. cruzi through the induction of a preferential metabolic pathway. In this work, we have studied in Mo the role of MR in arginase induction and in T. cruzi survival using different MR ligands. We have showed that pre-incubation of T. cruzi infected cells with mannose-Bovine Serum Albumin (Man-BSA, MR specific ligand) biased nitric oxide (NO)/urea balance towards urea production and increased intracellular amastigotes growth. The study of intracellular signals showed that pre-incubation with Man-BSA in T. cruzi J774 infected cells induced down-regulation of JNK and p44/p42 phosphorylation and increased of p38 MAPK phosphorylation. These results are coincident with previous data showing that Cz also modifies the MAPK phosphorylation profile induced by the parasite. In addition, we have showed by confocal microscopy that Cz and Man-BSA enhance MR recycling. Furthermore, we studied MR behavior during T. cruzi infection in vivo. MR was up-regulated in F4/80+ cells from T. cruzi infected mice at 13 and 15 days post infection. Besides, we investigated the effect of MR blocking antibody in T. cruzi infected peritoneal Mo. Arginase activity and parasite growth were decreased in infected cells pre-incubated with anti-MR antibody as compared with infected cells treated with control antibody. Therefore, we postulate that during T. cruzi infection, Cz may contact with MR, increasing MR recycling which leads to arginase activity up-regulation and intracellular parasite growth.  相似文献   

15.
In order to better understand the epidemiology of Human and Animal trypanosomiasis that occur together in sleeping sickness foci, a study of prevalences of animal parasites (Trypanosoma vivax, T. congolense "forest type", and T. simiae) infections was conducted on domestic animals to complete the previous work carried on T. brucei gambiense prevalence using the same animal sample. 875 domestic animals, including 307 pigs, 264 goats, 267 sheep and 37 dogs were sampled in the sleeping sickness foci of Bipindi, Campo, Doumé and Fontem in Cameroon. The polymerase chain reaction (PCR) based method was used to identify these trypanosome species. A total of 237 (27.08%) domestic animals were infected by at least one trypanosome species. The prevalence of T. vivax, T. congolense "forest type" and T. simiae were 20.91%, 11.42% and 0.34% respectively. The prevalences of 7 vivax and T. congolense "forest type" differed significantly between the animal species and between the foci (p < 0.0001); however, these two trypanosomes were found in all animal species as well as in all the foci subjected to the study. The high prevalences of 7 vivax and T congolense "forest type" in Bipindi and Fontem-Center indicate their intense transmission in these foci.  相似文献   

16.
The longevity and fecundity of inseminated and uninseminated females of four phytophagous mite species from the Indo-Pacific tropical area, Tetranychus fijiensis, T. lambi, T. marianae and T. neocaledonicus, were investigated. Uninseminated females of these species laid fewer eggs but lived longer than inseminated ones. The 50% survival rate of inseminated females was attained 20, 15.5, 14.5 and 13.5 days before that of uninseminated females in T. marianae, T. neocaledonicus, T. fijiensis and T. lambi respectively. Comparison between the egg production of inseminated and uninseminated females shows that the fecundity of inseminated females was roughly twice as great in T. marianae and T. fijiensis, 1.5 times as great in T. neocaledonicus and 1.25 times as great in T. lambi. The range of differences observed between species may perhaps result from adaptation to the climate of their area of origin.  相似文献   

17.
The effect of chitosan fragments with different degrees of polymerization and the chemical derivatives of chitosan differing in the number of amino groups and total molecule charge on phages T2, T4, and T7 was studied. The interaction of chitosan with bacteriophage particles inactivated them to the extent dependent on the chemical properties of chitosan and its concentration. Phage T2 was found to be most susceptible to inactivation by chitosan. The polycationic nature of chitosan plays an important role in the inactivation of phages. It is assumed that the abnormal rearrangement of the basal plate of phages, the loss of long tail fibers, and, probably, modification of the receptor-recognizing phage proteins may be responsible for the inactivation of coliphages by chitosan.  相似文献   

18.
本文报道了我国西南地区拟白蘑属Tricholomopsis Singer 8种1变种,其中2新种,1新变种和3个我国新记录种;新种是青盖拟白蘑T.lividipileata P.G.Liu和黑鳞拟白蘑T.nigrosquamosa P.G.Liu;新变种是竹生拟白蘑变种T.bambusina Hongo var.megasporaP.G.Liu;新记录种是南美杉拟白蘑 T.araucariae Sing.,丝囊拟白蘑T.flavissima(smith)Sing.和长根拟白蘑T.radicata(Pk.)Sing.。新种和新变种均有拉丁文描述和插图;本文所引证标本均存放于中国科学院昆明植物研究所隐花植物标本馆(HKAS)。  相似文献   

19.
Four species of Trichodoridae, two of them new and belonging to the T. aequalis complex, are reported from Alaska. Trichodorus carlingi n. sp. differs from all other species of the genus in having conspicuously hamate spicules. Vaginal sclerotizations are trapezoidal to rectangular. Trichodorus paucisetosus n. sp., which resembles T. sparsus Szczygiel, 1968 and T. nanjingensis Liu & Cheng, 1990, has sparsely setose, noncephalated spicules partially striated in one or two zones, oval to round vaginal sclerotizations, sperm in discrete spermathecae, and onchiostyle 57-72 μm long. Trichodorus californicus Alien, 1957 is reported from many sites in Alaska, and T. aequalis Allen, 1957 is reported from one site. Trichodorus californicus was collected almost exclusively from glacial refugial regions north of the Alaska Range.  相似文献   

20.
丘华兴  陈秀香   《广西植物》1992,12(3):209-214
<正> 广西的大戟科植物种类众多。作者对广西中草药原植物研究过程,将已采集的标本及华南植物所标本室(SCBI)和广东、广西主要标本室(均有注明)收藏的广西及其邻近地区的大戟科标本进行整理;现报道(一)、三宝木属植物摘记;有5种和3个新变种,其中广西产5种、1变种。(二)、广西白大凤属植物;1种。  相似文献   

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